From the Guidelines
The recommended duration of treatment for cellulitis is typically 5 days, but treatment should be extended if the infection has not improved within this time period. This recommendation is based on the most recent and highest quality study, which suggests that a 5-day course of antimicrobial therapy is as effective as a 10-day course, if clinical improvement has occurred by 5 days 1. For uncomplicated cellulitis, a 5-day course of antibiotics is often sufficient, while more severe cases may require longer treatment. Common antibiotic choices include cephalexin, dicloxacillin, or clindamycin for patients with penicillin allergies. If methicillin-resistant Staphylococcus aureus (MRSA) is suspected, trimethoprim-sulfamethoxazole or doxycycline may be used. Treatment should continue until clinical improvement is observed, including decreased redness, swelling, and pain. Patients should elevate the affected limb when possible, use warm compresses, and ensure adequate hydration. If symptoms worsen despite 48-72 hours of antibiotics, fever persists, or the infection spreads, medical reevaluation is necessary as intravenous antibiotics or hospitalization may be required.
Some key points to consider when treating cellulitis include:
- The use of antibiotics active against streptococci, such as penicillin, amoxicillin, or cephalexin 1
- The potential need for longer treatment courses in more severe cases or in cases where clinical improvement is not observed within 5 days 1
- The importance of monitoring for signs of clinical improvement, such as decreased redness, swelling, and pain 1
- The need for medical reevaluation if symptoms worsen or if the infection spreads, as intravenous antibiotics or hospitalization may be required 1
From the Research
Duration of Treatment for Cellulitis
The recommended duration of treatment for cellulitis varies depending on the severity of the condition and the patient's response to therapy.
- According to a study published in 2014 2, the recommended therapy duration for patients hospitalized with cellulitis is 10-14 days.
- However, a study published in 2004 3 found that 5 days of therapy with levofloxacin was as effective as 10 days of therapy for patients with uncomplicated cellulitis.
- Another study published in 2005 4 found that the addition of an oral anti-inflammatory agent to antibiotic treatment hastened the resolution of cellulitis-related inflammation.
Factors Affecting Treatment Duration
Several factors can affect the duration of treatment for cellulitis, including:
- Patient age: A study published in 2018 5 found that older patients required longer treatment durations.
- C-reactive protein levels: The same study found that higher C-reactive protein levels before treatment were associated with longer treatment durations.
- Presence of diabetes mellitus: Patients with diabetes mellitus required longer treatment durations, according to the 2018 study 5.
- Presence of blood stream infection: The 2018 study also found that patients with blood stream infections required longer treatment durations.
Route of Antibiotic Administration
The route of antibiotic administration (intravenous or oral) may not affect the outcome of treatment for cellulitis, according to a study published in 2020 6.
- The study found that patients who received only oral therapy were more likely to improve at day 5, and were as likely to return to normal activities at day 10 and day 30, compared to those who received intravenous therapy.
- However, the study also found that patients with more severe cellulitis were more likely to receive intravenous therapy.